Rekeyable master and user lock system with high security features
US4741188A · kind A · utility
Inventor
Key dates
| Filing date | Jul 16, 1985 |
| Grant date | May 3, 1988 |
| Priority date | — |
| Expiry date | Jul 16, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T70/774
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Methods and apparatus are disclosed for multiple level user and master key lock rekeying changes externally by the use of appropriately bidded level change keys. Several variations of methods and apparatus for removing user level change wafers to rekey user levels independent of master levels and to rekey master levels independent of user levels are disclosed. Some of the apparatus are suitable for locks wherein the cylinder is rotatable at 180.degree., and other embodiments are disclosed for locks wherein cylinder rotation is limited to less than 180.degree.. Further, apparatus for enhancing the security of such rekeyable locks are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.